This invention relates generally to means and apparatus for detecting a location of a vehicle, and more particularly to detecting the unsafe or illegal presence of a vehicle in a railroad grade crossing.
A majority of train-vehicle accidents at grade crossings occur when drivers ignore or do not observe warning systems such as gates, flashing lights, or warning signs. The railroad industry and state transportation authorities regularly engage in construction projects to increase the level of safety as these intersections, particularly drawing on accident statistics as a means of prioritizing potential improvement projects. With the advent of inexpensive monitoring systems that operate over channels on the nation""s cellular telephone infrastructure, a means exists by which data pertaining to crossing violations can be delivered to recipients who would find such information very valuable. Adding an effective means of detecting such an occurrence to a communications device requires a more precise detection device that can withstand wide temperature and environmental extremes faced in such an application while maintaining sharply bounded detection zones.
Previous means of accomplishing this task have been hindered by the cost and lack of precision of other detection technologies such as infrared, light beams and photocells, and microwave security intrusion sensors. The accuracy and repeatability of these technologies vary widely over time, temperature, and weather conditions. Ice, snow, rain, and dust can render them inoperative. Buried loops can detect vehicles, but they are costly to install and maintain, and do not detect pedestrian traffic.
In addition, it would be desirable if statistics of crossing violations could be accumulated over time for remote grade crossings. If such statistics were known, it may be possible to identify xe2x80x9cproblemxe2x80x9d crossings and to make changes to reduce the occurrence of violations.
In one embodiment, the present invention is therefore an alarm monitor for a railroad grade crossing, the grade crossing having an island activation relay that is activated in response to an approaching train, the alarm monitor including a micropower impulse radar (MIR) responsive to pedestrians and motor vehicles in a prohibited area of the crossing island during activations of the island activation relay; and a processor configured to generate a warning signal when the MIR detects a pedestrian or a motor vehicle in the prohibited area during an activation of the island activation relay.
It will be seen that embodiments of the present invention provide a cost-effective system for detecting and reporting instances of vehicles and pedestrians violating crossing warning systems. Using these embodiments, railroad industry and state transportation authorities can learn of elevated risk situations without waiting to compile accident statistics. With such information, better decisions can be made with respect to increased enforcement, implementation of alternate warning systems, or other remedies to reduce the likelihood of accidents.